The present invention relates to a waterproof electrical connector and a collective rubber stopper therefor.
A prior type of waterproof connector (see FIG. 6 of this specification) is configured as follows: a rubber stopper attachment hole 3 is provided in a posterior face of a connector housing 2 having a plurality of cavities 1 formed therein. This rubber stopper attachment hole 3 covers openings of all the cavities 1. A collective rubber stopper 5, which is fitted into the rubber stopper attachment hole 3, has electric wire through members 4 opening therein, the locations thereof corresponding to the cavities 1. The collective rubber stopper 5 is maintained in position by a rubber stopper pushing member 6. Terminal fittings 8, which have ends of electric wires 7 fixed thereto, are inserted into the cavities 1, widening the electric wire through members 4 of the collective rubber stopper 5 as they are pushed therethrough. Inner circumference faces of the electric wire through members 4 fit tightly and resiliently with outer circumference faces of the electric wires 7, thereby sealing each cavity 1. One example of this type of waterproof connector is described in JP 5-266941.
In the waterproof connector configured as described above, the electric wire 7 (shown in the lower row in FIG. 6) may, due to the waterproof connector being rotated, be led outwards in a manner whereby it is bent at a right angle to its axial direction. If a pulling force is exerted on the electric wire 7 that is in this state, the electric wire 7 will pull, on the side that is bent, on the inner circumference face of the electric wire through member 4, causing it to change shape resiliently and thus become larger, and a space S will be formed between the electric wire 7 and the opposite side of the inner circumference face of the electric wire through member 4. As a result, the seal thereof is compromised.
One means to avoid this problem is to make the rubber stopper 5 thicker. However, in that case, more space is required in which to attach this rubber stopper 5, thus causing the connector to become larger. Furthermore, this leads to greater resistance when inserting the terminal fittings 8 through the electric wire through members 4, thus making this insertion problematic. As a result, an effective solution to this problem is required.
The present invention has taken the above problem into consideration, and aims to improve the sealing function of a waterproof connector provided with a collective rubber stopper.
According to the invention there is provided a waterproofing stopper for a wire receiving opening of an electrical connector, said stopper comprising a body having an inner side, an outer side and a plurality of holes therethrough, said holes being sized to resiliently engage a respective electrical wire, characterised in that a ring like blind recess surrounds each of said holes at the outer side thereof.
Such a stopper provides that the relatively thin annular portion surrounding each wire can bend therewith; accordingly the risk of moisture entering the connector is reduced.
Preferably the blind recesses extend about halfway through the thickness of the stopper, and in one embodiment the wall thickness of the annular portion surrounding the wire is about the same thickness as the wire itself. This annular portion may be co-moulded of a relatively softer material so as to better follow the curvature of a belt wire, without causing the stopper to become unstable in the connector housing.